Subhasish Dey

Subhasish Dey (Bengali: শুভাশীষ েদ; born 1958) is a hydraulician and educator. He is known for his research on the hydrodynamics and acclaimed for his contributions in developing theories and solution methodologies of various problems on hydrodynamics, turbulence, boundary layer, sediment transport and open channel flow. He is currently a Professor of the Department of Civil Engineering, Indian Institute of Technology Kharagpur, where he served as the Head of the Department during 2013-15 and held the position of Brahmaputra Chair Professor during 2009-14 and 2015. He also holds an Adjunct Professor position in the Physics and Applied Mathematics Unit at Indian Statistical Institute Kolkata. Besides he has been named a Distinguished Visiting Professor at the Tsinghua University in Beijing, China.

Dey is an associate editor of Journal of Geophysical Research - Earth Surface, Journal of Hydraulic Engineering, Journal of Hydraulic Research, Sedimentology, Acta Geophysica, Journal of Hydro-Environment Research, International Journal of Sediment Research and Journal of Numerical Mathematics and Stochastics. He is also an editorial board member of several journals including the Proceedings of the Royal Society of London A: Mathematical, Physical and Engineering Sciences.

Dey was born to Bimalendu Dey (father) and Kana Dey (mother) in Jalpaiguri town, West Bengal, India in 1958. In 1987, he married Swastika Dey (née Talukdar); and they have a son, Sibasish, and a daughter, Sagarika.

Dey received B.E. degree in civil engineering from the University of North Bengal in 1981, MTech degree in water resources engineering and PhD degree in hydraulic engineering from the Indian Institute of Technology Kharagpur in 1984 and 1992, respectively. He started his professional career as a faculty of the National Institute of Technology, Durgapur, where he taught fluid mechanics and hydraulics from 1984 to 1998. Then, he joined as a faculty of the Indian Institute of Technology Kharagpur in 1998.

Dey has become a fellow of the Indian National Science Academy (FNA), Indian Academy of Sciences (FASc), National Academy of Sciences, India (FNASc) and Indian National Academy of Engineering (FNAE). He received the JC Bose Fellowship award in 2018. He is the Vice President of the Council of World Association for Sedimentation and Erosion Research (WASER) (2019–2022). He served as a Council Member of the World Association for Sedimentation and Erosion Research (WASER) (2011–2013) and the International Association for Hydro-Environment Engineering and Research (IAHR) (2015-2019). He is also a Member of the IAHR Fluvial Hydraulics Committee. Dey is ranked among the 150 most cited researchers in civil engineering in Shanghai’s Global Ranking of Academics.

He has developed various theories of hydrodynamics. He discovered the origin of the scaling laws of sediment transport and the onset of a straight river to meander. In turbulence, he developed universal probability density function for turbulent velocity fluctuations, Reynolds stress and conditional Reynolds shear stresses in wall-shear flows. In fluvial hydraulics, he has contributed fundamental theories of sediment thresholds (also known as initiation of motion), discovered existence of negative hydrodynamic lift and non-universality of von Kármán constant. He has made pioneering contributions to the mechanism of scour at hydraulic structures. Besides, he has developed theories of secondary boundary layer in curved pipes, wall jets, seeping bed flows and turbulent bursting etc.

• Dey, S. (2014). Fluvial Hydrodynamics: Hydrodynamic and Sediment Transport Phenomena. GeoPlanet: Earth and Planetary Sciences. Springer. ISBN 978-3-642-19061-2.